B BURGDORFERI FLAGELLA

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 运动是细菌致病的重要组成部分，而细菌鞭毛马达被认为是实现这一目的的最熟练的生物机器。质子通过马达的流动产生逆时针或顺时针方向的鞭毛旋转，分别导致平移运动或“翻滚”。尽管经过了几十年的研究，鞭毛马达旋转的确切机制仍然是一个谜。该提案的目的是利用高通量冷冻电子断层扫描(CRYO-ET)提供对鞭毛马达最详细的结构洞察，并将这些信息应用于鞭毛旋转和马达反转的可测试模型。这项工作将反过来为致病细菌和非致病细菌的运动机制提供分子基础。 伯氏疏螺旋体非常适合于这种类型的分析，因为1)它的直径很小(~0.2？m)，这是高分辨率冷冻所必需的；以及2)~3,600个转座子突变体的可用性。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Motility is an important component of the pathogenesis of bacteria and the bacterial flagellar motor is considered to be the most proficient biological machine for this purpose. The influx of protons through the motor produces either counterclockwise or clockwise flagellar rotation, resulting in translational motion or 'tumbling', respectively. Despite decades of research, the precise mechanism of flagellar motor rotation has remained a mystery. The purpose of proposal is to provide the most detailed structural insight into the flagellar motor using high-throughput cryo-electron tomography (cryo-ET), and to apply this information to a testable model of flagellar rotation and motor reversal. This work will in turn provide the molecular basis on the mechanism of motility in both pathogenic and nonpathogenic bacteria. Borrelia burgdorferi is ideally suited for this type of analysis because of 1) its small diameter (~0.2 ¿m), which is necessary for high resolution cryo-ET; and 2) the availability of ~3,600 transposon mutants.